// Copyright 2014 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. use std::cell::RefCell; use std::collections::BTreeMap; use std::env; use ast; use ast::{Ident, Name, TokenTree}; use codemap::Span; use ext::base::{ExtCtxt, MacEager, MacResult}; use ext::build::AstBuilder; use parse::token; use ptr::P; use util::small_vector::SmallVector; use diagnostics::metadata::output_metadata; // Maximum width of any line in an extended error description (inclusive). const MAX_DESCRIPTION_WIDTH: usize = 80; thread_local! { static REGISTERED_DIAGNOSTICS: RefCell = { RefCell::new(BTreeMap::new()) } } /// Error information type. pub struct ErrorInfo { pub description: Option, pub use_site: Option } /// Mapping from error codes to metadata. pub type ErrorMap = BTreeMap; fn with_registered_diagnostics(f: F) -> T where F: FnOnce(&mut ErrorMap) -> T, { REGISTERED_DIAGNOSTICS.with(move |slot| { f(&mut *slot.borrow_mut()) }) } pub fn expand_diagnostic_used<'cx>(ecx: &'cx mut ExtCtxt, span: Span, token_tree: &[TokenTree]) -> Box { let code = match (token_tree.len(), token_tree.get(0)) { (1, Some(&TokenTree::Token(_, token::Ident(code, _)))) => code, _ => unreachable!() }; with_registered_diagnostics(|diagnostics| { match diagnostics.get_mut(&code.name) { // Previously used errors. Some(&mut ErrorInfo { description: _, use_site: Some(previous_span) }) => { ecx.struct_span_warn(span, &format!( "diagnostic code {} already used", code )).span_note(previous_span, "previous invocation") .emit(); } // Newly used errors. Some(ref mut info) => { info.use_site = Some(span); } // Unregistered errors. None => { ecx.span_err(span, &format!( "used diagnostic code {} not registered", code )); } } }); MacEager::expr(ecx.expr_tuple(span, Vec::new())) } pub fn expand_register_diagnostic<'cx>(ecx: &'cx mut ExtCtxt, span: Span, token_tree: &[TokenTree]) -> Box { let (code, description) = match ( token_tree.len(), token_tree.get(0), token_tree.get(1), token_tree.get(2) ) { (1, Some(&TokenTree::Token(_, token::Ident(ref code, _))), None, None) => { (code, None) }, (3, Some(&TokenTree::Token(_, token::Ident(ref code, _))), Some(&TokenTree::Token(_, token::Comma)), Some(&TokenTree::Token(_, token::Literal(token::StrRaw(description, _), None)))) => { (code, Some(description)) } _ => unreachable!() }; // Check that the description starts and ends with a newline and doesn't // overflow the maximum line width. description.map(|raw_msg| { let msg = raw_msg.as_str(); if !msg.starts_with("\n") || !msg.ends_with("\n") { ecx.span_err(span, &format!( "description for error code {} doesn't start and end with a newline", code )); } // URLs can be unavoidably longer than the line limit, so we allow them. // Allowed format is: `[name]: https://www.rust-lang.org/` let is_url = |l: &str| l.starts_with('[') && l.contains("]:") && l.contains("http"); if msg.lines().any(|line| line.len() > MAX_DESCRIPTION_WIDTH && !is_url(line)) { ecx.span_err(span, &format!( "description for error code {} contains a line longer than {} characters.\n\ if you're inserting a long URL use the footnote style to bypass this check.", code, MAX_DESCRIPTION_WIDTH )); } }); // Add the error to the map. with_registered_diagnostics(|diagnostics| { let info = ErrorInfo { description: description, use_site: None }; if diagnostics.insert(code.name, info).is_some() { ecx.span_err(span, &format!( "diagnostic code {} already registered", code )); } }); let sym = Ident::with_empty_ctxt(token::gensym(&format!( "__register_diagnostic_{}", code ))); MacEager::items(SmallVector::many(vec![ ecx.item_mod( span, span, sym, Vec::new(), Vec::new() ) ])) } pub fn expand_build_diagnostic_array<'cx>(ecx: &'cx mut ExtCtxt, span: Span, token_tree: &[TokenTree]) -> Box { assert_eq!(token_tree.len(), 3); let (crate_name, name) = match (&token_tree[0], &token_tree[2]) { ( // Crate name. &TokenTree::Token(_, token::Ident(ref crate_name, _)), // DIAGNOSTICS ident. &TokenTree::Token(_, token::Ident(ref name, _)) ) => (*&crate_name, name), _ => unreachable!() }; // Output error metadata to `tmp/extended-errors//.json` if let Ok(target_triple) = env::var("CFG_COMPILER_HOST_TRIPLE") { with_registered_diagnostics(|diagnostics| { if let Err(e) = output_metadata(ecx, &target_triple, &crate_name.name.as_str(), &diagnostics) { ecx.span_bug(span, &format!( "error writing metadata for triple `{}` and crate `{}`, error: {}, \ cause: {:?}", target_triple, crate_name, e.description(), e.cause() )); } }); } else { ecx.span_err(span, &format!( "failed to write metadata for crate `{}` because $CFG_COMPILER_HOST_TRIPLE is not set", crate_name)); } // Construct the output expression. let (count, expr) = with_registered_diagnostics(|diagnostics| { let descriptions: Vec> = diagnostics.iter().filter_map(|(code, info)| { info.description.map(|description| { ecx.expr_tuple(span, vec![ ecx.expr_str(span, code.as_str()), ecx.expr_str(span, description.as_str()) ]) }) }).collect(); (descriptions.len(), ecx.expr_vec(span, descriptions)) }); let static_ = ecx.lifetime(span, ecx.name_of("'static")); let ty_str = ecx.ty_rptr( span, ecx.ty_ident(span, ecx.ident_of("str")), Some(static_), ast::Mutability::Immutable, ); let ty = ecx.ty( span, ast::TyKind::FixedLengthVec( ecx.ty( span, ast::TyKind::Tup(vec![ty_str.clone(), ty_str]) ), ecx.expr_usize(span, count), ), ); MacEager::items(SmallVector::many(vec![ P(ast::Item { ident: name.clone(), attrs: Vec::new(), id: ast::DUMMY_NODE_ID, node: ast::ItemKind::Const( ty, expr, ), vis: ast::Public, span: span, }) ])) }